Buying DVD's

There is no standard method of labelling a DVD Video disc packaging to show the features present on the disc itself. This page offers a guide to what all DVD's should display relating to audio format, screen aspect ratio, and extra features, so that you are less likely to buy discs that don't meet your expectations.




The most important feature of DVD for most people is the sound format, especially if you have invested in equipment with Dolby Digital processing. DVD's come with one of three basic sound types - either a full-on 5.1 channel digital surround track (such as DTS and Dolby Digital), a stereo track or, on some older movies, a single-channel mono track. Finding out which sound type is on a DVD before you buy is not as easy as it should be (in some cases) due to the poor way in which DVD features are displayed on the package. The actual sound options may be shown as graphical icons or text, or both. Although there are several ways that producers describe a DVD's audio content, they all have common factors to look out for.

One of the best methods is the sound icons shown below. They make it clear what sound format it present by using solid blocks to represent the audio channels:  
  Other sound formats are represented by the icone shown in the diagram above. There will always be a text description on a DVD cover that states which format is in use:  

Look out for the following information on the DVD package to ensure you get the sound you need:



Look for the text '5.1' or 'AC-3 5.1' or 'Digital Surround', together with the Dolby Digital logo and/or the 5.1 channel icon shown above. Unless you know that a DVD has a 5.1 soundtrack (from a disc review, for example) beware of discs that display the Dolby Digital logo and nothing else - some DVD's show the logo to say that the DVD format is compatible with Dolby Digital technology, but it's no guarantee that a 5.1 track is present. If you don't have a Dolby Digital decoder in your system, a 5.1 channel soundtrack will be 'down-mixed' into either a two-channel stereo track or a four-channel surround track, depending on whether you are using a Pro-Logic decoder or not.


DTS 5.1

Look out for '5.1', 'Digital Surround' or the above 5.1 channel icon, together with the DTS Digital Surround logo.



Two-channel stereo tracks come in a few different variants, including Dolby Digital 2.0, Dolby Surround, Dolby Pro-Logic and MPEG2 Stereo. All stereo soundtracks will work with Dolby Pro-Logic hardware to give 4-channel surround sound. Discs marked with 'Dolby Surround' or 'Dolby Pro-Logic' will produce the best results because they have dedicated centre and surround channel information contained within the main stereo track. Normal stereo sound can still be presented by Pro-Logic hardware by creating a rear and front-centre channel.



Found on older classic movies or re-releases of classic TV shows from before the common use of stereo or multi-channel theatre sound. Look out for the above icon or the 'Mono' text. Some extras found on DVD may contain either mono, stereo or Pro-Logic surround soundtrack - it is unusual to find extra features that have a 5.1 mix like the main feature presentation.



You should always find a note on the packaging that tells you the Aspect Ratio of the picture on the disc. This will normally be 16:9, 1.85:1 or 2.35:1, although other less common sizes are available. If only one of the above ratios is displayed, the picture can be expanded for viewing on a widescreen TV. On a normal 4:3 television, the picture will be shown as a Letterbox frame, with the black borders at the top and bottom of the picture. Some DVD's are supplied with a 4:3 aspect ratio, perfect for 4:3 televisions, but resulting in borders at the sides of a widescreen television. 4:3 versions will usually be described as '4:3', 'Regular' or 'Full-Frame'. There may also be two aspect ratios shown, commonly 4:3 plus a widescreen ratio. In this case, each side of the disc has a different option to suit the type of television you are using. Look out for widescreen DVD's that have been "Enhanced for 16:9 televisions" - these are usually 'anamorphic' widescreen presentations where the letterbox picture has been vertically pre-stretched and therefore maintaining the best possible picture quality. The widescreen TV only needs to expand the picture horizontally, so vertical screen resolution is unaffected.



The box below shows the 'features' found on the Polygram DVD "Trainspotting". It's a good example of how a DVD package should be presented to show clearly what can be found on the disc.


SUBTITLE TRACKS - Lists the different subtitle options in different languages, and shows on which track number they are found.


VIDEO ASPECT RATIO - What screen sizes are available. This disc has a 'full-frame' picture for 4:3 televisions on side 1, and a 16:9 widescreen picture for widescreen televisions on side 2.

MULTIPLE VIEWING ANGLE - Only available on some discs, this DVD has only 1 angle.  
REGION CODE - This shows that this disc will only play on Region 2 and Region 4 DVD players using the PAL colour system. This is important if you use a player that can play other regions, or a player that has been imported and won't play Region 2 or 4 discs.  
AUDIO CONTENT - Apart from the Aspect Ratio, the audio content is the most important consideration to most DVD users. No problems with this disc - Dolby Digital 5.1 channel surround sound is included in three languages. Notice that the package displays the Dolby Digital logo, the "5.1" text and the 5.1 channel logo. As a rule, all DVD's carry the Dolby Digital logo. But beware of discs that don't also state that the sound is "5.1" or displays the box-logo - these may be normal stereo or even mono.  


This next cover is from "Bad Boys". Although it looks different from the one above, all the information you need is there.


SOUND - You can be sure that the sound is Dolby Digital 5.1 - the logos, icons and text is there. There's also a dedicated Dolby Surround soundtrack for use with Pro-Logic equipment. Notice that the icon for the Surround soundtrack has no centre channel displayed - but Pro-Logic equipment will still present a centre audio channel if a centre speaker is in use.


PICTURE - The aspect ratio is shown as 1:1.85 widescreen. There is no reference to a 4:3 ratio so you know that it will appear as a 1:1.85 letterbox when viewed on a 4:3 television. Notice the interesting note at the bottom of the box-out. DVD's that have the phrase "Enhanced for 16:9 widescreen TV's" are presented in anamorphic widescreen picture, the best format for DVD.

PICTURE - 4:3 ratios fill a 4:3 television. Widescreen ratios will be viewed on a 4:3 television as a Letterbox picture, or can be expanded to fill the full width of a widescreen television. Unless the package states that a 4:3 option is available, only the widescreen version is included. 16:9 ratios will fill a widescreen completely, while other widescreen formats will display small black borders above and below the screen. Discs marked 'Enhanced' will be anamorphic widescreen, while others could be either anamorphic or letterbox, where the television's 'zoom' feature must be used.  
SOUND - Dolby Digital 5.1 is shown by the Dolby Digital logo PLUS either the text "5.1" or the digital surround 5.1 icon. The Dolby Digital logo on its own is no guarantee that a 5.1 track is available. Dolby Digital 5.1 can be heard as stereo (through two speakers) or as Pro-Logic surround (using two rear speakers and a front centre speaker). Dolby Digital 2.0 Stereo or other stereo formats will work with Pro-Logic equipment to provide analogue surround sound. "AC-3" is sometimes used to describe a Dolby Digital soundtrack, but this should be complemented by the 5.1 text or the icon.